Aromatic vs. acyclic dienyl propargyldicobalt cations: Preparation and comparative reactivity

ORGN 35

James R. Green, jgreen@uwindsor.ca and Sheida Amiralaei, amirala@uwindsor.ca. Department of Chemistry and Biochemistry, University of Windsor, 401 Sunset Ave., Windsor, ON N9B 3P4, Canada
The stability of propargyl cations caused by the presence of a hexacarbonyldicobalt complex has several ambiguities, particularly pertaining to the effect of substituents at the propargylic site. In order to shed light onto these questions, we have prepared the complex [1] and investigated the Nicholas-type reactions of its generated 'dehydrotropylium ion' complex [2] with nucleophiles of varying strength. By way of comparison, the acyclic dienyl propargyl alcohol complex [3] has been prepared and the analogous reactions of its derived cation [4] studied.